全文获取类型
收费全文 | 1075117篇 |
免费 | 71572篇 |
国内免费 | 1367篇 |
专业分类
耳鼻咽喉 | 15015篇 |
儿科学 | 34608篇 |
妇产科学 | 28635篇 |
基础医学 | 153407篇 |
口腔科学 | 29564篇 |
临床医学 | 94919篇 |
内科学 | 203647篇 |
皮肤病学 | 24392篇 |
神经病学 | 81453篇 |
特种医学 | 42969篇 |
外国民族医学 | 201篇 |
外科学 | 163106篇 |
综合类 | 21704篇 |
现状与发展 | 1篇 |
一般理论 | 263篇 |
预防医学 | 74603篇 |
眼科学 | 24539篇 |
药学 | 86152篇 |
7篇 | |
中国医学 | 2806篇 |
肿瘤学 | 66065篇 |
出版年
2019年 | 7756篇 |
2018年 | 11302篇 |
2017年 | 8911篇 |
2016年 | 10101篇 |
2015年 | 11264篇 |
2014年 | 15277篇 |
2013年 | 22207篇 |
2012年 | 30561篇 |
2011年 | 32305篇 |
2010年 | 18954篇 |
2009年 | 17817篇 |
2008年 | 29956篇 |
2007年 | 32080篇 |
2006年 | 32706篇 |
2005年 | 31038篇 |
2004年 | 29733篇 |
2003年 | 28555篇 |
2002年 | 27531篇 |
2001年 | 60021篇 |
2000年 | 61478篇 |
1999年 | 50929篇 |
1998年 | 12447篇 |
1997年 | 11001篇 |
1996年 | 11016篇 |
1995年 | 10320篇 |
1994年 | 9342篇 |
1993年 | 8858篇 |
1992年 | 37792篇 |
1991年 | 36274篇 |
1990年 | 35744篇 |
1989年 | 34286篇 |
1988年 | 30865篇 |
1987年 | 29987篇 |
1986年 | 28215篇 |
1985年 | 26448篇 |
1984年 | 19186篇 |
1983年 | 16113篇 |
1982年 | 8822篇 |
1979年 | 17029篇 |
1978年 | 11404篇 |
1977年 | 10229篇 |
1976年 | 8837篇 |
1975年 | 10068篇 |
1974年 | 11651篇 |
1973年 | 11273篇 |
1972年 | 10754篇 |
1971年 | 10092篇 |
1970年 | 9252篇 |
1969年 | 8938篇 |
1968年 | 7917篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168
Background
Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.Methods
We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).Results
Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.Conclusions
Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation. 相似文献83.
84.
85.
86.
Brenda Laky Isabella Alram Julia K. Frank Leo Pauzenberger Werner Anderl Karl-Heinz Wagner Philipp R. Heuberer 《Journal of orthopaedic research》2020,38(9):2074-2082
Increasing numbers of arthroplasties are also accompanied by postoperative infections. The main purpose was to evaluate preoperative serum bilirubin levels between patients with and without infections after shoulder and knee arthroplasties. For this retrospective case-control single-center study, a total of 108 patients were extracted from a prospectively collected database. Eighteen patients with infections after shoulder (n = 8) and knee (n = 10) arthroplasty were matched by age, gender, and implant type in a 1:5-scenario to 90 patients (40 shoulders and 50 knees) without postoperative infection. Demographic data, preoperative blood parameters, and postoperative infection-related outcomes were evaluated. Total bilirubin was the only preoperative parameter significantly different between the infection (8.21 ± 3.25 μmol/L or 0.48 ± 0.19 mg/dL) and noninfection (10.78 ± 4.62 μmol/L or 0.63 ± 0.27 mg/dL; P = .014) group, while C-reactive protein and other liver parameters were similar between the groups. Significantly more controls (92.1%) had preoperative bilirubin levels above 8.72 μmol/L or 0.51 mg/dL than cases (7.9%; P = .007). The 5-year infection survival-rate was 65.6% for patients with preoperative bilirubin levels < 8.72 μmol/L or < 0.51 mg/dL and 91.2% with ≥ 8.72 μmol/L or ≥ 0.51 mg/dL. Mildly decreased preoperative bilirubin levels with a cutoff at 8.72 μmol/L or 0.51 mg/dL were significantly associated to patients with infections after shoulder and knee arthroplasty. There were no differences in other blood parameters or comorbidities between patients with infections and their matched-controls. 相似文献
87.
Regina K. Rowe David M. Pyle J. David Farrar Michelle A. Gill 《European journal of immunology》2020,50(10):1550-1559
Rhinovirus (RV) infections are linked to the development and exacerbation of allergic diseases including allergic asthma. IgE, another contributor to atopic disease pathogenesis, has been shown to regulate DC antiviral functions and influence T cell priming by monocytes. We previously demonstrated that IgE-mediated stimulation of monocytes alters multiple cellular functions including cytokine secretion, phagocytosis, and influenza-induced Th1 development. In this study, we investigate the effects of IgE-mediated stimulation on monocyte-driven, RV-induced T cell development utilizing primary human monocyte-T cell co-cultures. We demonstrate that IgE crosslinking of RV-exposed monocytes enhances monocyte-driven Th2 differentiation. This increase in RV-induced Th2 development was regulated by IgE-mediated inhibition of virus-induced type I IFN and induction of IL-10. These findings suggest an additional mechanism by which two clinically significant risk factors for allergic disease exacerbations—IgE-mediated stimulation and rhinovirus infection—may synergistically promote Th2 differentiation and allergic inflammation. 相似文献
88.
C. Lukannek S. Shaefi K. Platzbecker D. Raub P. Santer S. Nabel H.S. Lecamwasam T.T. Houle M. Eikermann 《Anaesthesia》2019,74(9):1165-1174
Postoperative pulmonary complications are associated with an increase in mortality, morbidity and healthcare utilisation. The Agency for Healthcare Research and Quality recommends risk assessment for postoperative respiratory complications in patients undergoing surgery. In this hospital registry study of adult patients undergoing non-cardiac surgery between 2005 and 2017 at two independent healthcare networks, a prediction instrument for early postoperative tracheal re-intubation was developed and externally validated. This was based on the development of the Score for Prediction Of Postoperative Respiratory Complications. For predictor selection, stepwise backward logistic regression and bootstrap resampling were applied. Development and validation cohorts were represented by 90,893 patients at Partners Healthcare and 67,046 patients at Beth Israel Deaconess Medical Center, of whom 699 (0.8%) and 587 (0.9%) patients, respectively, had their tracheas re-intubated. In addition to five pre-operative predictors identified in the Score for Prediction Of Postoperative Respiratory Complications, the final model included seven additional intra-operative predictors: early post-tracheal intubation desaturation; prolonged duration of surgery; high fraction of inspired oxygen; high vasopressor dose; blood transfusion; the absence of volatile anaesthetic use; and the absence of lung-protective ventilation. The area under the receiver operating characteristic curve for the new score was significantly greater than that of the original Score for Prediction Of Postoperative Respiratory Complications (0.84 [95%CI 0.82–0.85] vs. 0.76 [95%CI 0.75–0.78], respectively; p < 0.001). This may allow clinicians to develop and implement strategies to decrease the risk of early postoperative tracheal re-intubation. 相似文献
89.
Erin L. Sutfin Jennifer Cornacchione Ross Allison J. Lazard Elizabeth Orlan Cynthia K. Suerken Kimberly D. Wiseman 《Health communication》2019,34(3):343-351
ABSTRACTAdolescents and young adults smoke waterpipe tobacco (WT) and cigarillos, at least in part, based on erroneous beliefs that these products are safer than cigarettes. To address this challenge, we used a systematic, three-phase process to develop a health communication campaign to discourage WT and cigarillo smoking among at-risk (tobacco users and susceptible non-users) 16- to 25-year-olds. In Phase 1, we used a national phone survey (N = 896) to determine salient message beliefs. Participants reported constituents (i.e., harmful chemicals) emitted by the products were worrisome. In Phase 2, we developed and evaluated four message executions, with varying imagery, tone, and unappealing products with the same constituents, using focus groups (N = 38). Participants rated one execution highly, resulting in our development of a campaign where each message: (1) identified a tobacco product and constituent in the smoke; (2) included an image of an unappealing product containing the constituent (e.g., pesticides, gasoline) to grab attention; and (3) used a humorous sarcastic tone. In Phase 3, we tested the campaign messages (17 intervention and six control) with a nationally representative online survey (N = 1,636). Participants rated intervention and control messages highly with few differences between them. Exposure to messages resulted in significant increases in all risk beliefs from pre to post (p < 0.05). For WT, intervention messages increased beliefs about addiction more than control messages (p < 0.05). This systematic, iterative approach resulted in messages that show promise for discouraging WT and cigarillo use. 相似文献
90.
Umar Nadia K. Badshah Maaz B. Sandrasegaran Kumar Ghabril Marwan Agarwal Saurabh Tann Mark Lacerda Marco Kwo Paul Y. 《Digestive diseases and sciences》2015,60(7):2196-2200
Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be... 相似文献